Scraper unit for endless moving surfaces



April 17, 1951 w. F. SPANG SCR=APER UNIT FOR ENDLESS MOVING SURFACESFiled July 17, 1948 lfwezzfow:

iii

mma F E6 1mm f 2 Patented Apr. 17, 1951 SCRAPER UNIT FOR ENDLESS MOVINGSURFACES William F. Spang, Miltonj Mass assignor to Cube Steak Machine00., Needham Heights, Mass.,' a

partnership Application July 17, 1 948, Serial No. 39,360

This invention relates to a novel cleaning unit for endless movingsurfaces such as wheels, band saws, etc. Smooth and efficient running ofsuch apparatus requires that these surfaces which come into cooperatingcontact shall be kept free a tangential position which has not performedthe desired operation efficiently. I have discovered that a cleaningunit disposed substantially normal to the surface to be cleaned willperform 1 Claim. (01. 143-29) duced inner end of the detent 28. It willbe apparent that this circular construction of the plunger [6 and thecooperating bore within the block provide a structure that can beproduced economically and with great precision. This constructiontogether with the one-piece block 20 provides a strong and superiorsupport for resisting the cutting thrusts against the the cleaningoperation in superior manner and the primary object of my inventionresides in the production of an improved unit thus constructed andoperated for this purpose. These and other features of the inventionwill be best understood and appreciated from the following descriptionof a preferred embodiment thereof selected for purposes of illustrationand shown in the accompanying drawings in which;

Fig 1 illustrates diagrammatically a band saw unit employing myinvention,

Fig. 2 is a rear end elevation of my improved surface cleaning unit,

Fig. 3 is a side elevation thereof, partially in section, and

Fig. 4 is a plan elevation, partially in section. In Fig. 1 I haveillustrated a band saw l0 supported on three wheels or rolls l2. Thecooperating surfaces of the saw and wheels must be kept free from dirt,grit and the like if the cooperating parts are to function efficiently.Jihe improved unit M which I have invented for performingllhlSifllllCtiOn is mounted to operate at an angle normal to the surfacebeing cle' ed tooth J8 .terminates in a sharp cutting ed g e;."l9.

The block 2|] is open at its forward end to receive the plunger and itsrear end is provided with a hole 22 for receiving the smaller rear end24 of the plunger. A compression spring 26 normally forces the plungerforwardly and a detent 23 is provided for holding the plunger againstrotation. As illustrated in Fig. 2 the forward portion, I6, of theplunger is circular in cross section and has a longitudinal key slottherein receiving the replunger and provides for quick and easy assemblyand disassembly of the unit. The block 20 is supported in a bracket 3|]provided with a spring pressed detent 32 for holding it within thebracket.

Each wheel I 2 illustrated in the drawing has a saw supporting periphery33 grooved circumferentially and the cutting extremity IQ of the toothI8 is formed to fit this grooved surface as shown in Fig. 4. The bracket30 and block 20 support the plunger I6 for sliding movement normal tothe surface to be cleaned. The tooth [8 has a top surface 34 extendingrearwardly from the cutting extremity l9 and disposed in a planesubstantially normal to the surface 33 and a bottom surface 35 divergingfrom the top surface from the extremity l9 rearwardly. Thus the tooth l8provides a sharp cutting edge always held in cutting contact with thesurface 33 by the spring 26 and adapted to keep the surface 33 clean ofall foreign matter that would interfere with the operation of themachine.

The block 20 can be removed for repair or replacement merely byreleasing the detent 32 and the plunger is freely removable forwardlyfrom the block. The invention therefore provides a unit which can beeasily removed and replaced and which serves the intended function withmaximum efficiency.

Havingthus disclosed my invention, I claim as new and desire to secureby Letters Patent:

A scraper unit for endless moving surfaces,

comprising a one-piece block having a straight bore circular in crosssectionextending thereinto from its forward face to an end wall at therear face and a boreof reduced diameter through the wall coaxial withthe-first bore, a plunger slidable longitudinally in the bores andhaving a forward portion fitting the larger bore and a rear portionfitting the smaller bore, the forward portion of the plunger having akey slot longitudinally therein, a releasable detent extending into thekey slot and preventing rotation of the plunger but permitting itsmovement longitudinally, a scraping tool with a sharp cutting extremityon the forward end of the plunger outside of the bore, resilientmeans-normally forcing the plunger forwardly, a support disposed outsideof and having an opening therein receiving and closely fitting theblock, and a releasable detent carried by the support for engaging andholding the block in place therein.

WILLIAM F. SPANG.

REFERENCES CITED UNITED STATES PATENTS Name Date Ide Nov. 28, 1871Number Number 10 Number Name Date Hoffman Dec. 17, 1889 Chamberlain Aug.19, 1930 Jinnett Feb. 21, 1933 Biro May 18, 1937 Blank July 23, 1940BiIO 1 July 1, 1947 FOREIGN PATENTS Country Date Great Britain July 7,1921

